[Effect of aromatic amino acids on levorin biosynthesis].

Aromatic amino acids, such as tryptophan and phenylalanine inhibit biosynthesis of levorin, while tyrosine stimulates it. The studies with resting cells showed that the changes in the level of the antibiotic production in the presence of the above amino acids were connected with their effect on the process of levorin biosynthesis and not on the growth of the antibiotic-producing organism. The changes in the content of the bound p-aminoacetophenone in the mycelium of Str.